JPH01199056A - Oscillation generating device - Google Patents

Abstract

PURPOSE:To have setting of characteristics according to the intended use by forming No.1 and No.2 cam surfaces alternately in the cam rotating direction, and moving the positions of a cam follower, rotational drive shaft, and swing shaft within specified ranges. CONSTITUTION:A disc 6 with cam followers 3a, 3b are installed at the end of an oscillating shaft 2. A top T and a bottom B are formed at cams 5a, 5b mounted on rotational drive shafts 4a, 4b, wherein the cam followers 3a, 3b make to bothways per turn of the cams 5a, 5b. Accordingly the cam followers 3 move within an extent set by the relation L1>L2>L3, where L2 is the distance of the center of cam follower 3a from the center O2 of the oscillating shaft 2, L3 is the distance from O1 to O2, and L1 is the distance of the center of cam follower 3a from O2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vibration generating device L1, and particularly relates to a vibration generating device suitable for use in a cam follower, particularly a vibration testing machine, etc.

[Prior Art] Conventionally, as an example of a vibration generating device, one using a crank mechanism has been proposed.

In a swing generating device using this crank mechanism, one end of a connecting rod is rotatably attached to a position radially apart from the rotation center of the crankshaft, and the other end of the connecting rod is attached to a position radially apart from the rotation center of the crankshaft. It has a structure in which it is rotatably attached to a position spaced apart in the radial direction from the center of swing of the swing shaft.

The rotational motion of the crankshaft is converted into reciprocating motion of the connecting rod, and the reciprocating motion of the connecting rod is further converted into the rocking motion of the swing shaft.

[Problems to be Solved by the Invention] By the way, in the swing generating device having the above-described configuration, L1 is obtained by changing the length of the connecting rod, and the swing angle of the cam follower swing shaft and the accompanying angular velocity can be changed. The adjustment range is only limited to changing the angular velocity and angular acceleration, and the change patterns of these angular velocities and angular accelerations are only similar to -, and the configuration is such that these change patterns can be changed appropriately, , it is desired to obtain large angular acceleration.

The present invention aims to solve these problems.

゛ [Means for Solving the Problems] In order to solve the above-mentioned problems, the swing generation device according to the present invention includes a swing shaft, and a swing shaft that is spaced from the swing center in the swing radial direction. A cam follower provided as a cam follower, a rotation drive shaft provided along the swing axis, and a cam that is integrally attached to the rotation drive shaft and rotated in a plane parallel to the movement plane of the cam follower. , the cam surfaces formed on the outer circumferential portion of the cam include at least a pair of first cam surfaces that guide the cam follower in a direction away from the rotational drive shaft, and a cam surface that guides the cam follower in a direction that approaches the rotational drive shaft. and at least a pair of second cam surfaces guiding the cam follower, the first cam surfaces and the second cam surfaces are formed alternately in the rotational direction of the cam,
And, the cam follower is a cam follower with a distance between the cam follower and the rotational drive shaft being L1, and a distance between the cam follower and the swing axis is L1, and the cam follower is a cam follower,
Furthermore, the distance between the swing shaft and the rotational drive shaft is L1, and the cam follower is characterized in that it can be moved within a range set by the relationship Lr+Lx>L.

[Effect]

According to the present invention, the profile of the first and second cam surfaces of the cam is changed or each of these cam surfaces is increased, and the moving speed of the cam follower guided thereby or the oscillation per one rotation of the cam is changed. By changing the number of reciprocations of the moving axis, it is possible to arbitrarily set the pattern of angular velocity and angular acceleration. Further, by setting the movement range of the cam follower to L1, a larger angular acceleration is obtained by changing the rate of change of the cam follower angular velocity.

[Example] Hereinafter, an example of the present invention will be described based on FIGS. 1 and 2.

In the figure, the symbol l indicates the vibration generating device according to this embodiment,
A swinging shaft 2, and a pair of cam followers 3 (3m/3b) provided on the swinging shaft 2 at a distance from the swinging center OI in the swinging radial direction and at a predetermined angle a interval in the swinging direction. and a pair of rotation drive shafts 4 (4a-4b) provided along the length direction of the swing shaft 2 on both sides of the swing shaft 2 and the cam followers 301 and 3b), and A pair of cams 5 (5a-5b) are attached to the drive shaft 4 (4m, 4k) and rotated in a plane parallel to the cam followers 301, 3b) (7) movement plane, and each of the cams The cam surface C formed on the outer circumferential portion of 5 (Ss and Sb) is a pair of first cam surfaces that guide the cam followers 3 (31 and 3b) in a direction away from each of the rotational drive shafts 4 (41-4b). A cam surface L1 consisting of a cam surface C1 and at least a pair of second cam surfaces C8 that guide the cam follower 3 (3a-3b) in a direction approaching the rotational drive shaft 4 (41-4b), and the cam follower and these The first cam surface C1 and the second cam surface C3 are connected to the cam 5 (5
1 and 5b) are formed alternately in the rotational direction.

Next, to explain these details, the swing shaft 2 is swingably attached to a base plate (not shown) and is connected to L1.
As shown in FIG. 1, a disk 6 is integrally attached concentrically to the end of the cam follower, and each of the cam followers 3 (3!, 3b) is attached near the peripheral edge of this disk 6. It is being

These cam followers 30 & 3b) are constituted by rolling elements rotatably supported by the disk 6.

Each of the rotation drive shafts 4 (41, 4b) is disposed near the disk 7 in parallel to the swing shaft 2, and is rotatably supported by the substrate. These rotary drive shafts 4 (4a, 4b) are connected in opposite directions (in the illustrated example, one rotary drive shaft 4a is clockwise and the other rotary drive shaft 4b is counterclockwise). ) A drive mechanism (path shown) for synchronous rotation is connected.

As shown in FIG. 1, each of the cams 5 (51, sb) attached to the rotational drive shaft 4 (41, 4b) has a top portion T at two locations spaced at a predetermined pitch in the rotation direction. A bottom part B is formed in the middle part of these top parts T.

These top portions T and bottom portions B are continuous by a gentle curve, and the outer peripheral edge thereof is the cam surface C.

Further, in this embodiment, the cam 5 (S
The front side in the rotational direction of 1.sb) is the first cam surface C8, and the rear side in the rotational direction is the second cam surface C1.

Therefore, the cam follower 3 (31, 3b) that is brought into sliding contact with the cam surface C alternately rotates on the first cam surface C1 and the second cam surface C3 as the cam 5 (5M@Sb) rotates. The rotary drive shaft 4 (4!・4
In contrast to b), the cam 5 (sl, 5b) can reciprocate twice per revolution, with the difference in height between the top portion T and the bottom portion B as the stroke.

On the other hand, the shape of the cam surface C of the one cam 5 is such that the center of one cam follower 3a and the center of one rotational drive shaft 41 are 0. When the distance to Ll is set to satisfy the following equation.

Ll-A+MX S i n (2θ) however, A; Reference circle of cam Ss, M: Distance between top part T and bottom part B and reference circle θ; Rotation drive shaft 4 angle; are shown respectively.

The shape of the other cam 5b is determined by the trajectory of the other cam follower 3b at this time and the trajectory of the other cam follower 3b when the cam Ss is rotated once while holding one cam follower 31 in contact with the cam surface C of the one cam S1. It is set based on the rotational position of the rotational drive shaft 4M and the rotational position of the other rotational drive shaft 4b that is rotated synchronously.

Furthermore, the center of the one cam follower 31 and the swing shaft 2
Distance L from the center of oscillation O1! is the swing center O of the swing axis 2
I and one rotational drive shaft 4 center 0. and the distance L3 between the center of the cam follower 3a and the center of the rotational drive shaft 41 0! The distance from the cam follower is L1, and the relationship with the cam follower is
It is set to satisfy the following formula.

Ll + t, > Ls Next, the operation of this embodiment will be explained.

First, when the re-rotation drive shafts 4 are rotated at a constant speed in opposite directions (one rotation drive shaft 4a clockwise and the other counterclockwise) from the position shown in FIG. The cam follower 3a is moved in the direction away from the rotary drive shaft 41 by the first cam surface C1 of one cam Sa, and this movement continues until the cam follower 3'a reaches the top part °T of the cam 51. be exposed.

On the other hand, the cam follower 3b that is in contact with the other cam sb is set to L1 because the other cam sb is rotated in the opposite direction in synchronization with the one cam 5a. is guided toward the other rotary drive shaft 4b by the second cam surface C3 of the
This continues until the cam follower 3b reaches the bottom portion B of the other cam sb.

With this operation, L1 is established, and the cam follower swing shaft 2 is moved to the first position.
In the figure, it is oscillated from the maximum oscillation position in the clockwise direction to the maximum oscillation position in the counterclockwise direction.

When both cams 5 continue to rotate further, the first cam surface CI of the other cam 5b moves the other cam follower 3b in the direction of separating it from the other rotational drive shaft 4b, contrary to the above. and one cam follower 3a is guided in a direction approaching one rotation drive shaft 4a by the second cam surface C8 of one cam S1, thereby causing the swing shaft 2 to swing clockwise. It will be done.

From then on, the swing shaft 2 rotates at a rate of 2 reciprocations per rotation of both cams 5.
is shaken.

During such a rocking operation, the rocking of the rocking shaft 2 is determined by the shape of the cam surface C of the cam 5, that is, the profile, so by changing the profile of the cam 5, various rocking movements can be performed. A dynamic pattern can be obtained.

On the other hand, the movement range of the cam follower 31 is set to the above-mentioned range and is set to L1, and within the range of this condition, the cam follower L, +L, is set to L1, and by moving closer to the cam follower, it is set to L1, and the cam follower is set to L1 as described above. The angular acceleration obtained at the cam 5 increases.

As shown in Figure 2, this means that L, +L, is L1,
This is thought to be due to the fact that the change in the swing angle given to the swing shaft 2 by the cam follower cam 5 becomes L1 by moving it closer to the cam follower, and the rise of the swing angle change given to the swing shaft 2 by the cam follower cam 5 becomes steeper. is small).

However, if these are set too close together, for example, so that they are the same, then on the contrary, a swing generating device using such a cam 5 will not work.

This is because, as shown by curve C in FIG. 2, a change point occurs at a change time of 0 seconds.

Note that the layers, dimensions, etc. of each component shown in each of the above embodiments are merely examples, and can be variously changed based on design requirements and the like.

〔Effect of the invention〕

As explained above, the vibration generating device according to the present invention is
a swing shaft, a cam follower provided on the swing shaft at a distance from the center of swing in the swing radius direction, a rotary drive shaft provided along the swing shaft, and a cam follower integrated with the rotary drive shaft. a cam attached to the cam follower and rotated in a plane parallel to the movement plane of the cam follower, and a cam surface formed on the outer circumference of the cam at least guides the cam follower in a direction away from the rotational drive shaft. L1 includes a pair of first cam surfaces and at least a pair of second cam surfaces that guide the cam follower in a direction approaching the rotational drive shaft; are formed alternately in the rotational direction of the cam, and the cam follower has a distance between the cam follower and the rotation drive shaft as Ll, a distance between the cam follower and the swing shaft as L1, and is a cam follower; The distance between the shaft and the rotation drive shaft is L1, and as a cam follower, L, + L
, ) L. By changing the shape of the cam surface of this cam, L1 is set, and the moving speed of the cam follower, that is, the swing axis Characteristics such as the swing angle, angular velocity, and angular acceleration can be set arbitrarily, and the characteristics can be easily set according to the purpose of use. By changing the rate of change of angular velocity, L1 can be This provides excellent effects such as being able to increase the angular acceleration of the swing axis.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention,
FIG. 1 is a front view schematically showing the main parts, and FIG. 2 is a characteristic curve diagram. DESCRIPTION OF SYMBOLS 1... Swing generator, 2... Swing shaft, 3... Cam follower, 4... Rotation drive shaft, 5... Cam, C...
-Cam surface, C3...Φ1st cam surface, c,...second cam surface. Applicant: Mitsuba Electric Manufacturing Co., Ltd. Five-time teaching angle shown in Figure 1 and Figure 2

Claims (1)

[Claims] a swing shaft, a cam follower provided on the swing shaft at a distance from the center of swing in the swing radius direction, a rotary drive shaft provided along the swing shaft, and a cam follower integrated with the rotary drive shaft. a cam attached to the cam follower and rotated in a plane parallel to the movement plane of the cam follower, and a cam surface formed on the outer circumference of the cam at least guides the cam follower in a direction away from the rotational drive shaft. It consists of a pair of first cam surfaces and at least a pair of second cam surfaces that guide the cam follower in a direction approaching the rotational drive shaft. The cam followers are formed alternately in the rotational direction, and the distance between the cam follower and the rotational drive shaft is L_1, the distance between the cam follower and the swinging shaft is L_2, and the distance between the swinging shaft and the rotational drive shaft is L_2. Let the distance of L_3 be L_1+L
A vibration generating device characterized by being able to move within a range set by the relationship _2>L_3.